1. Field of Invention
The present invention relates, in general, to a structure for mounting a piston ring, and, more particularly, to a structure for mounting a piston ring, which when a plurality of piston rings is mounted around a piston head, allows end gaps formed in the piston rings to rotate at different sections in a circumferential direction of the piston head, thereby preventing the end gaps from being aligned and thus reducing a blow-by gas.
2. Description of Related Art
Generally, a phenomenon “blow-by” occurs when a small amount of fuel-air mixture escapes between a cylinder wall and a piston during normal operation of an internal combustion engine, and the fuel-air mixture is referred to as “blow-by gas”.
Such blow-by occurs in most automobiles, and a piston ring and engine oil perform a sealing function in order to minimize blow-by.
FIG. 1 shows a structure for mounting piston rings according to the related art.
Referring to FIG. 1, a plurality of ring grooves 1a is formed along a circumferential direction of a piston head 1, and piston rings 2 are respectively fitted into the ring grooves 1a. Here, the piston ring is provided with an end gap 2a in the form of a partially-cut section. The piston rings 2 are freely rotated in ring grooves 1a during normal operation of an engine.
However, when end gaps of the piston rings coincide with each other during rotating operation, an amount of blow-by gas considerably increases to cause turbo fouling and degradation in post-treatment.
In order to solve this problem, a technique in which stoppers are formed in the ring grooves so as to prevent the piston rings from rotating has been proposed. However, in this case, since the piston rings cannot rotate, one-sided wear of a piston and adhesion of piston rings occur and therefore a scuffing phenomenon occurs on the piston.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.